Nasal Carriage of Methicillin-Resistant Staphylococcus aureus (MRSA) among Healthcare Workers in a Tertiary Care Hospital in New Delhi, India
Keywords:
MRSA, Healthcare Workers, Meca, MSSA, Β-Lactam Antibiotics.Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen with a high prevalence among healthcare workers (HCWs), posing a risk of transmission to vulnerable patients. Colonized HCWs are often asymptomatic but serve as reservoirs for hospital and community-associated infections. This study aims to determine the nasal carriage rate of MRSA among HCWs at HAHC Hospital, analyze its antimicrobial resistance profile, and detect the presence of mecA and PVL genes. A cross-sectional study at HAHC Hospital, Jamia Hamdard, New Delhi, India, collected nasal swabs from 250 HCWs and MBBS students, culturing isolates to identify and test S. aureus for antimicrobial susceptibility. MRSA screening was performed using the cefoxitin disc diffusion method, and polymerase chain reaction (PCR) was used for mecA and PVL gene detection. The prevalence of S. aureus nasal carriage was 31.6% (79/250), with MRSA accounting for 5.6% (14/250). The MRSA rate among S. aureus carriers was 17.7% (14/79). The highest MRSA carriage was observed in nursing staff (16.7%; 5/30), followed by doctors (6.4%), laboratory technicians (5.8%), and MBBS students (3.7%). Housekeeping staff showed no MRSA carriage. MRSA isolates exhibited 100% resistance to levofloxacin and cefoxitin, followed by ciprofloxacin (78.5%), erythromycin (64.2%), clindamycin (57.1%), and gentamicin (42.8%). The mecA gene was detected in 13 out of 14 MRSA isolates, while the PVL gene was absent. Significant MRSA nasal carriage among nursing staff and final-year MBBS students underscores the urgent need for infection control, regular screening, and delocalization strategies.
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